I don't know if they make a 2" or 2 1/2" for the back, but I gotta say that I'm very happy with my Rancho 44044 2 1/2" springs I got for the front. Ride seems nice so far. Not too hard. I think it looks good with my stock size (29") tires, and I think* it may fit 31's.
I bought mine used from another member. New, I think I saw they are around $100-175 apiece depending on where you get them.
Here's a pic after install on my Wagon with new stock size tires:
1990 Grand Wagoneer-"Big Jeep"
AMC 360, TF727, NP229, 2.72 gears, 2" lift
Rancho 44044 springs, Rusty's 2" AAL, TFI w/ MSD C/R
...not too rusty anymore